21127351680 has 384 divisors, whose sum is σ = 75204249120. Its totient is φ = 5462360064.

The previous prime is 21127351673. The next prime is 21127351697. The reversal of 21127351680 is 8615372112.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48792744 + ... + 48793176.

Almost surely, 2^21127351680 is an apocalyptic number.

21127351680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21127351680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37602124560).

21127351680 is an abundant number, since it is smaller than the sum of its proper divisors (54076897440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21127351680 is a wasteful number, since it uses less digits than its factorization.

21127351680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698 (or 683 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 21127351680 in words is "twenty-one billion, one hundred twenty-seven million, three hundred fifty-one thousand, six hundred eighty".